By Torin Douglas BBC media correspondent

It's 40 years since the launch of the Sun - the most consistently influential British newspaper of modern times.

Yet the paper has been reluctant to celebrate the birthday - and with good reason.

Brief history of Page Three

For the Sun that was launched on 15 September 1964 was not the "super soaraway Sun" of the 70s, the Sun which rewrote the tabloid rulebook and "Wot Won It" for the Tories in the 1992 General Election.

In fact, the original Sun was launched partly to stop that sort of populist, right-wing paper and, ironically in hindsight, to protect the position of the established Labour tabloid, the Daily Mirror.

The 1964 Sun was a broadsheet with high aspirations and ideals, based on copious market research.

It billed itself as "the newspaper born of the age we live in", and was designed to tap into the lifestyle changes of the 60s - the rise of the young and upwardly-mobile, including career-oriented women.

Unashamedly downmarket

The broadsheet Sun was launched by IPC to replace the Daily Herald, a trade union broadsheet making big losses.

THE SUN RISES 1964 - launched as broadsheet based on Daily Herald 1969 - New owner Rupert Murdoch launches tabloid 1970 - After 12 months, Page Three girls remove tops 1978 - Sales of four million overtake the Mirror's 1982 - 'Gotcha' headline marks sinking of Belgrano 1989 - Hillsborough disaster 1992 - It's 'The Sun Wot Won It' for John Major 1997 - The Sun backs Blair

Because IPC also owned the left-of-centre Daily Mirror - then Britain's most successful tabloid, with almost 5 million sales - it didn't want to launch a head-on competitor.

But the losses continued and in 1969 the Sun was sold to Rupert Murdoch, who relaunched it as a brash, unashamedly downmarket tabloid.

Under its first editor, Larry Lamb, it followed a popular formula - sex, sport and sensation.

It wasn't new, but the Sun went further than its rivals. When it ran a picture of a topless girl, later putting it on Page 3, a social institution was born.

Frivolous content

Fulfilling the adage that no one went broke underestimating the taste of the public, the Sun's sales soared, while those of the Mirror - which had started to take itself rather seriously, with a pull-out analysis section called 'Mirrorscope' - fell away.

In 1978 the Sun overtook the Mirror to become Britain's biggest-selling daily paper - and it also became the most influential, setting an irreverent tabloid agenda that was to rub off both on broadsheets and broadcasters in years to come.

The papers' political leanings have wielded great influence

Despite its predominantly frivolous content, the Sun also acquired significant political influence, thanks to its penetration of the all-important C2 voters (the skilled working class).

It took political reporting and comment seriously, and at the General Election of 1979, it helped Margaret Thatcher sweep the Conservatives to power.

The Sun hadn't always been Conservative. It proclaimed no allegiance, preferring to describe itself simply as 'radical'.

In the 1970 election it had supported the Labour Prime Minister Harold Wilson.

When he lost unexpectedly, it switched its support to his Tory successor Ted Heath, later losing faith with both sides.

But in Mrs Thatcher it found a true radical, backing her to the hilt as she vowed to take on the trade unions.

It was Larry Lamb who came up with the headline 'Winter of Discontent' to sum up the strikes that dogged the Labour Government and on polling day in 1979 the Sun came out firmly for the Tories.

Lamb was rewarded with a knighthood in the New Year Honours List.

Belligerent note

Another, very different editor embodied the Sun in its heyday - the legendary Kelvin McKenzie.

In the Thatcherite 80s, the paper struck a harsher, more belligerent note. McKenzie dominated the paper with his energy and flair for a story and a headline, constantly administering "bollockings" to those staff who failed to meet his demanding standards.

During the Falklands War, the Sun became a cheerleader for Mrs Thatcher with headlines such as "Stick it up your Junta" and, after the sinking of the General Belgrano, "GOTCHA".

Even McKenzie acknowledged that this headline went too far, removing it in later editions.

But his biggest misjudgement - for which the Sun was still apologising earlier this year - was over the Hillsborough stadium disaster in 1989 in which 96 football fans died.

The paper claimed Liverpool fans had picked the pockets of victims and beaten up a policeman. There was an immediate boycott and sales in the city have still not fully recovered.

Commercial sales

In the 1992 election campaign, the Sun ruthlessly ridiculed the Labour leader Neil Kinnock and McKenzie later claimed it was the "the Sun wot won it" for John Major.

During the Falklands War the paper backed Thatcher

Tony Blair and Alastair Campbell decided that if Labour were ever to win, they must at least neutralise the paper. They succeeded beyond their hopes, winning its backing both in 1997 and 2001.

Yet in recent years the Sun has lost much of its confidence and its instinctive ability to make a splash, unlike its sister paper the News of the World.

The Mirror's Piers Morgan - until his recent departure - was the editor grabbing the exclusives, even though that didn't translate into sales and commercial success.

Rebekah Wade, the current Sun editor, has yet to make a similar mark.

The Sun comfortably outsells the Mirror and remains hugely profitable.

But its sales are down more than 5% year-on-year, and since it found itself in the new Labour camp, its heart has not really seemed in it.

It backed Blair on Iraq but remains fervently anti-Europe, and can't bring itself to love the new Tory leadership.

Forty years on, the brash young upstart is showing its age.

Your comments:

As a newspaper boy in 1969, I did a morning newsround and had only one customer for the Sun, a retired dockyard worker who was never seen, being a recluse. I hadn't got back to the gate from pushing the tabloid version through his door when he came running out demanding to know why I had delivered the wrong paper. When I explained that this was the new style paper he said "Tell 'em if I wanted to read the Mirror I'd order it, cancel the bugger and I'll take the Morning Star instead" and he did till he died.
Nic, Havant

Yes the Sun may have Page Three and silly stories about hamsters etc but its political views are among the most sensible and decent in Fleet Steet. The Sun does not pander to terrorists or the cultures that encourage hate and calls a spade a spade, something that the BBC, Guardian and Independent could all learn from. I read the Telegraph but have tremendous respect for the Sun.
Julian , London England

The Sun has always had an over-inflated opinion of its own influence. It wasn't the Sun wot won it for the Tories in 1992, just as the same as it wasn't the Sun that got Labour into power five years later. The paper likes to portray itself as politically influential, but all it really does is follow the mood of the nation.
Tom, London

I think more than anything, the Sun sums up the political age of the me me me, now now now brigade. It's manipulation of its readers is deplorable, its journalistic standards lay in the gutter. If it was a person, the Sun would be soccer yob, lagered up and starting its sentences with ...I'm not racist, but...
Jon, England

As a gay adolescent I recall reading the headlines in the sun about the "Gay Plague" and all the ensuing coverage on HIV/AIDS. This publication has done more to stigmatise gay people and those with HIV than any other publication in this country. That's not even mentioning other minority groups who have probably suffered at this publications hands.
Gary, London, UK

Interesting, but why haven't the corny puns been mentioned? I once decided to count the number of puns in a copy of the Sun and came to about 50. No other newspaper comes close to this feat.
Ian, Marseille, France

I hate The Sun. For me it stands for everything that is bad about this country. It shamelessly whips up public emotion for its own ends and dives into commenting on issues it has no real understanding of. It attempts to gauge public opinion and frequently gets it wrong. Their 'You the Jury' phone polls used to make me laugh, I remember once they asked their 'army of readers' if cannabis should be legalised. To their undoubted horror the majority of readers voted yes. The results of the vote appeared the next day tucked between mobile phone ads on page 22 or thereabouts and warranted about 20 words.
Jason, Nottingham

I don't buy the Sun (I get the Times) but I do on occasion read it and I find it much preferable to the other tabloids and although its sometimes incredibly trashy I dont feel it takes itself as seriously as rubbish like the Daily Mail and Express which are far worse in my opinion.
Jen, Chester

The Sun is a national institution. The great headlines always raise a smile and the varied content is fantastic. If you don't like it, don't read it. Quite simple Really.
Jonny, Edinburgh

I agree completely with Jason and Jon. The Sun represents yob culture, yet shamelessly changes its views to sell more papers. It has done huge damage to our society by encouraging ignorance and a lack of respect for other people.
Richard P, London, UK

It's not allowed in my house since them comments on the Hillsborough disaster... the paper is a joke.
Jim, Liverpool

The Sun has never managed a full and unreserved apology for its shameful stories that followed Hillsborough in 1989. Whether acts of the paper or simply just the editor - the paper should have had the guts to offer a proper apology earlier in the year when the opportunity presented itself rather than simply issuing further insults to the people of Liverpool and its rival the Mirror.
Ian Agass, Stevenage

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